There was a chassis cutoff point sometime in the early production of the 400E which makes it difficult to get the correct brake parts the first time. The best thing to do is to get the part number off of the brake rotors on the car to get the correct parts. If you have a V8 and a chassis number of 124034 then you have a 400E. All 400Es have 4 piston front calipers but there is a difference in the rotors.

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Mercedes Benz Master Tech - Retired